More than 70 cases identified in Huron-Perth during ongoing Ontario measles outbreak

By Galen Simmons, Local Journalism Initiative Reporter

Local public-health officials are continuing to do everything they can to curb the spread of measles in Huron and Perth counties as the number of identified cases continues to rise both locally and across the province.

Huron Perth Public Health (HPPH) Medical Officer of Health Dr. Miriam Klassen and her team are working around the clock to curb the spread of measles in both counties as part of the provincewide response to the outbreak that first arrived in Ontario in October 2024.

“On Oct. 18, 2024, there was an exposure through a travel-related case in New Brunswick that was then connected to Ontario and introduced measles into Ontario,” Klassen said. “While New Brunswick declared their outbreak over on Jan. 7, 2025, unfortunately in Ontario that was not the case. From Oct. 18 – that first introduction – to April 2, there have been a total of 661 measles cases involving 13 health units.

“For HPPH, we reported our first measles case on Feb. 28, but quickly there were several others and it was apparent that local spread was happening among people who live, work and play in Huron-Perth. As of April 2, we are reporting 73 confirmed and probable cases, and I can tell you in the next weekly report, there will be more.”

Measles is a highly contagious virus. It is airborne and can remain in the air and on surfaces for up to two hours. The virus can spread to other people when someone with measles coughs, sneezes, talks, or breathes. Measles can result in complications such as diarrhea, ear infections and pneumonia. Rarely, measles can cause brain inflammation, respiratory failure and death.

Measles symptoms begin seven to 21 days after exposure to the virus and include:

• fever

• runny nose

• cough

• red eyes (watery)

• small white spots on the inside of the mouth and throat (not always present)

• a red, blotchy rash on the face initially, and then spreads down the body (normally appears three to seven days after symptoms begin).

Someone who has measles can be contagious from four days before the rash starts until four days after the rash starts. Most people fully recover from measles within two to three weeks, but sometimes measles can cause complications. Rarely, those who contract measles can develop subacute sclerosing panencephalitis – a progressive, disabling and deadly brain disorder – seven to 10 years after recovering from their initial infection.

“In Ontario, measles has been rare and that’s because Canada successfully eliminated measles in 1998 … and that happened as a result of high immunization coverage,” Klassen said. “So, while there are still occasional imported cases, those would be quickly contained without a lot of community spread.

“Prior to the COVID pandemic, the average number of measles cases in Ontario ranged between seven and 22. So, very infrequent. … Now, as observed around the world, … vaccination rates have been declining. That was happening before due to increased vaccine hesitancy, and then during COVID, vaccination rates fell even more because of decreased capacity (and) decreased access in a lot of places to vaccines as people all around the world redeployed for the COVID response.”

As a result of decreased vaccination rates globally, more cases of measles are being introduced to Canada and Ontario from abroad. Since Ontario’s vaccination rate has also decreased, measles has quickly spread across the province, with most new cases in Ontario now resulting from spread within and between communities like those in Huron-Perth.

“That’s because there are people who are un- or under-vaccinated due to reasons such as medical reasons, kids are too young to be vaccinated and also conscience or religious beliefs,” Klassen said. “So unfortunately, there are more individuals and clusters of people like that now, and once measles is introduced, it spreads very easily. It’s very, very contagious.”

With the rising number of measles cases identified in Huron-Perth, both counties are considered areas of concern. HPPH is hosting measles vaccine clinics for infants, children and people born in or after 1970 who are not up to date – the people who are most at-risk for contracting measles. Meanwhile, HPPH communicates information about infection prevention and control, testing advice, and vaccination recommendations with the public and its health-care partners, and primary care doctors are ordering more measles vaccines and sharing important information with their patients.

HPPH completes case management and contact tracing for confirmed cases of measles, similar to the process employed by local public-health officials when cases of COVID-19 were discovered during the pandemic.

“For every confirmed case of measles that is reported to us … we contact that person and provide advice about their own care, when to seek medical advice, how to isolate and ensure they’re not spreading the infection, and then also their contacts. We try to reach out to all contacts, find out if they’re up to date on immunization or not and provide them advice on what to watch for, if they’re eligible for … treatment to try and prevent them developing infection, … and then what they can do to help prevent further spread of the illness,” Klassen said.

Anyone who believes they have been exposed to measles should report to HPPH by calling 1-888-221-2133 ext. 3299 and follow public-health advice. Until they are contacted by public-health officials, they should do the following:

• stay home, avoid contact with other people and avoid having visitors in their home;

• if medical care is needed, call ahead before attending a health-care facility to inform staff of the potential measles exposure so they can prepare and prevent the virus from spreading to others; and

• wear a well-fitted mask while leaving home for medical care.

“The main difference between COVID and measles is COVID was a brand-new virus,” Klassen said. “No one had immunity and we didn’t have a vaccine, and we didn’t fully understand it either – we were learning as we went along. Whereas with respect to measles, we have a good understanding of this virus and we have a very effective vaccine with a proven track record. … Really, for most people the risk is low. For people who are up to date with their measles vaccination, we know it’s 97 per cent effective in preventing a measles infection. No vaccine is 100 per-cent effective, but people who have been vaccinated who develop the disease, which is not very common, tend to have a milder disease and less onward transmission.

“Adults born before 1970 are generally considered to have natural immunity. They likely contracted the virus in childhood. Individuals born in or after 1970 ought to check their vaccine record to make sure they have two doses of measles-containing vaccine.”

People who are at higher risk for contracting measles include those who are pregnant, people with weakened immune systems and children younger than five, particularly those who are two and younger.

For more information on measles in Huron-Perth, visit www.hpph.ca/health-topics/diseases-viruses-and-illnesses/measles/#.